From Longman Business Dictionary
simulationsim·u·la·tion /ˌsɪmjəˈleɪʃən/ noun [countableC, uncountableU] an activity or situation that produces conditions which are not real, but have the appearance of being real, used especially for testing somethingA computer simulation allows project engineers to study in detail the manufacturing process operations at the factory site.
—simulate verb [transitiveT]The Project Management Game simulates a design and build project on a compressed time scale.
—simulator noun [countableC]A new computer simulator has been designed to teach drivers how to handle a skid.